Swedged end push rod



Sept. l5, 1931. 1. o. ALMEN swEDGED END PUSH Ron Filed Aug'. 9, 1950 Patented Slept. 15, 1931v UNITED STATES PATENT OFFICE ,JOI-IN O. lALMEN, 0F ROYAL OAK, MICHIGAN, ASSIGNOR T0 GENERAL MOTORS RE- f SEARCH CORPORATION, 0F DETROIT, MICHIGAN, A CORPORATION OF DELAWARE SWEDGED END PUSH ROD Application iled August 9, 1930. Serial No. 474,230.

This invention has to do with push rods used on internal combustion engines to transmit thrust yin valve operating gear. It has therefore been proposed to make such push rods in the form of hollow tubes provided at their ends with ball shaped fittings for cooperation with the sockets in the rocker or cam follower. Such rods are preferable to solid rods because of reduction in weight, but the fittings must be separately manufactured and secured to the tube, increasing the cost of manufacture. Y y

According to my invention the push rods are made of tubular stock, slightly longer lthan required, and the excess metal is spun or formed over to provide spherical bearing surfaces; In some cases it may alsobe 'desirable to form an annular shoulder at the end of the rod to form a seat for the spring used to hold the push rod in its socket.

In Figure 1 I have shown a vertical section through a portion of an engine having my improved push rod incorporated in the valve Oear.

D Figure 2 is a vertical section through the push rod.

Figure 3 is a fragmentary section through the lower end of a modified form of push rod and its cam follower.

In Figure 1, 10 indicates a portion of the cylinder of an internal combustion engine. In the head of the cylinder are mounted the usual intake and exhaust valves, one of which is indicated at 12, held upon its seat by the usual coil spring 14. The valve is opened by means of the cam 16, pushing upward the cam follower 18, and push rod 420 to rock the rocker 22, the rocker moving the valve away from its seat.

Theimproved push rod 20, shown in detail in Figure 2, is made of tubular stock alittlelonger than the finished rod, as indicated by the dotted lines 21 in Figure 2. The ends of the rod are provided with spherical surfaces to engage the socket 23 formed in the stud 24 secured in the end of the rocker 22, and the socket 26 formed in the cam follower 18. The spherical ends are' made by spinning or by die-forming the ends of the tube. This operation results in slightly thickening the ends of the push rod as indicated on the drawmg.

In the modification shown on Figure 3, I have shown the lower end of the push rod formed to provide an annular shoulder 30. A spring 31 between the shoulder and the end of the guide 32 for the cam follower 18 holds the end of the push rod in the socket in the 1 cam follower and also causes the cam follower stantially closed spherical end, the walls of the tube at said end being circumferentially continuous.

3. A push rod in the form of a hollow cylindrical tube having one end formed outwardly and then inwardly to provide an annular seat, the walls of the tube at the extreme end having converged inwardly to provide a circumferentially continuous spherical end.

In testimony whereof I aiix my signature.y

JOHN O. ALMEN.

CERTIFICATE OF CORRECTION.

Patent No. 1,823,419. September l5, 1951.

JOHN O. ALMEN.

lt is herebyoertiiied that error appears in the printed specification of the above numbered patent requiring; correction as follows: Page l, line '79, claim 5, for "having" read being; and. that the said Letters Patent should be read with this correction therein that the same may conform to the record of the oase in the Patent Office.

Signed and sealed this 21st day of January, A. D. 1936.

I Leslie Frazer ('Seal) Acting Commissioner of Patents. 

